This invention relates to a method of preparing character data of alphabets, numerical digits, Chinese characters, Japanese cursive syllabaries, etc. (hereinafter they are generally termed "characters") for use in a sewing machine, and more particularly to a method of preparing intercharacter control data for use in an electronically controlled sewing machine.
As a result of recent development of a computer sewing machine, the restriction upon stitching various patterns has been removed, and it has become possible to stitch various characters such as alphabets, Japanese cursive syllabaries and numerical digits which requires many complex stitches. Since these characters are memorized as stitch control data in the sewing machine, the sewing machine may be used to individually stitch initials of names and moreover, to stitch a plurality of characters in series in any desired combination of characters. When continuously producing a combination of characters, it is required that each letter should be well balanced with beautiful form as well as uniform spacing between two adjacent letters.
For example, as shown in FIG. 3, where a top segment .alpha. and a bottom segment .beta. which define a region to be traversed by the sewing machine needle, are drawn respectively passing through the top and bottom portions of respective characters in parallel with each other in the material feeding direction, and where front segment X and rear segment Y are drawn to pass mostly projecting front and rear ends respectively of the characters in perpendicular to the top and bottom segments .alpha. and .beta., the characters may be arranged as shown in FIG. 1, for example, with the spacing (a) between the front segments X maintained at a constant value. However, according to this method of arranging the characters, the spacing (r) between the rear segments Y of respective characters and the front segments X of the next characters would not be the same as shown in FIG. 1. Of course, such nonuniform arrangement of the characters is not preferable.
According to another method which obviates this defect, the spacing (b) between the rear segments Y of respective characters and the front segments X of the next characters may be made constant, as shown in FIG. 2. The arrangement of the characters according to this method is considerably improved over that according to the first mentioned method. However, the areas (x), which are dotted and bounded by the outsides or contours of respective characters and segments X, .alpha. and .beta. are different from the areas (y), which are dotted and horizontally lined, and bounded by segments Y, .alpha. and .beta. and the outsides or contours of respective characters. Therefore, when the characters are stitched with a reduced spacing (b) as shown in FIG. 2, the spacing between ornamental letter patterns C and A seems to be broader than the spacing between patterns B and C as shown in FIG. 3, which means unsatisfactory character arrangement.